Your solar panels are probably facing the wrong way

The conventional wisdom about solar panels — the ones that don’t move as the sun does, at least — is that they should face south, catching rays from the east in the morning and the west in the afternoon. But a new study says that’s wrong: Solar panels should simply face west. Gizmodo writes:

Researchers at the Pecan Street Research Institute did a study of homes with solar panels in Austin, Texas and found that when homeowners faced solar panels west they were able to generate 2% more electricity in a day. And they also generated more electricity in the afternoon, when power grids experience peak demand.

And there’s another benefit to west-facing solar panels, too: They help save more money on electricity.Quartz:

[Q]uantifying the way that favoring late-day sunlight helps homeowners save money and utilities flatten out demand could lead to a simple but effective hack for the world’s solar installers: Simply re-orienting solar panels could shorten the amount of time it takes for them to pay for themselves.

This is less than helpful advice for people who’ve got their panels locked down in some specific configuration on a slanted roof. But it’s good advice for anyone who’s still looking to install one — or can get up on their roof and re-orient the ones they’ve already got.